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71.
72.
This paper critically reviews recent research exploring risk and protective factors for the development of problematic substance use in populations of young people. Specific populations of young people who are most vulnerable to developing problematic patterns of use are identified, and alterations to methods of data collection which would improve the ability of local authorities to monitor these populations and more efficiently target them for early preventative interventions are highlighted. It is argued that social‐psychological research techniques and approaches should be used to complement a risk and protection‐focused approach in order to improve the design and evaluation of interventions, and provide decision‐aids for practitioners when assessing the needs of vulnerable young people. Examples are provided to demonstrate the utility of social psychology in this regard, and the paper concludes with specific recommendations for future research and services. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
73.
文章从水稻强化栽培体系在四川省Y村推广初期取得良好效果之后未能得到可持续应用的现象出发,以SRI为例分析了导致新型现代农业技术话语弱化的因素及其对新型现代农业技术推广和应用产生的不利影响.研究发现,推广主体权力的弱化和农户对知识体系的模糊性认识导致新型现代农业技术无法建构起有效的话语,而农民在考虑到技术“比较效益”之后选择的外出务工和“消遣经济”的道路,则进一步弱化了新型现代农业技术话语,同时,也对我国农业经济的发展和进步造成了严重影响.  相似文献   
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75.
Reducing non-marital childbearing and making nonresidential fathers take greater responsibility for their children were identified as goals of numerous policy changes since the 1980s. Child-support award rates for children born to unmarried parents have been quite low historically, leading lawmakers to focus on increasing both award and payment rates for this group. Nonmarital fathers are also much less likely to have contact with their children. Although evidence suggests that policy efforts increase child support awards and receipt, the link between child support policies, child support outcomes, and father-child contact has received less attention. This paper uses data from the Survey of Income and Program Participation on children born between 1985–1997 to investigate the relationship between child-support award and receipt and the amount of contact that fathers have with their non-residential children. Since it is likely that both of these behaviors are, in part, determined by unobservable characteristics of the father, we estimate an instrumental variables Tobit model. The model is identified by our assumption that child support policy variables can impact child support awards and payments, but father-child contact cannot be directly legislated. Our results suggest that there are unintended, but desirable effects of child support establishment and collection. Policies to collect child support not only increase financial resources to families, but through their impact on payments increase visitation and contact between these children and their fathers. The estimated impact of receiving child support on contact is more than 27 days per year.An earlier version of this paper was presented at the Annual Meetings of the American Economic Association, Washington DC, January 2003 and the Annual Meetings of the Association of Public Policy and Management, November 2003. Support from NICHD Grant # HD30944 is gratefully acknowledged. We would like to thank Suzann Eshleman for excellent computer programming and James Scully for providing us with data on genetic testing laws.  相似文献   
76.
Although many researchers have explored the topic of dating violence, limited attention has been paid to female perpetrators. Very little research has examined variables that facilitate aggression for females in dating relationships. In an effort to investigate distinct types of violent behavior, the present study separated females who experience dating violence into three categories (bi-directional aggression, perpetrator-only, and victim-only) and compared them with a control group not previously exposed to interpersonal violence. The purpose of this study was to examine variables that discriminate violent females from non-violent females. Variables that were hypothesized to be associated with aggressive behavior and investigated in the current study were interparental aggression, self-esteem, love attitudes, and alcohol use. Three hundred female college students responded to multiple self-report questionnaires examining psychological correlates of dating violence. Females in the bi-directional aggression group were more likely to have witnessed their father abuse their mother and scored significantly lower on a measure of self-esteem than non-violent controls. Females in the control group demonstrated higher scores on a measure of mature and selfless love style than did the victim or perpetrator-only participants. There were no significant group differences regarding general alcohol consumption. Implications for prevention and intervention are presented and discussed.  相似文献   
77.
The error catastrophe theory of aging, proposed by Orgel in 1963, predicted a decrease in the fidelity of information transfer that accelerated as aging progressed, until properly functioning macromolecules could no longer be reliably made. The theory was extensively tested by comparing DNA polymerases, transfer RNAs, and proteins derived from aging versus young animals, but it did not prove to have general applicability to the process of aging. Recently, the heritable eye disorder progressive external ophthalmoplegia has been found to result from mutation of the gene encoding DNA polymerase gamma, which replicates mitochondrial DNA. The mutant form of the polymerase replicates DNA less accurately than the wild-type enzyme, providing an explanation for the accumulation of mutations in the mitochondrial DNA of patients with this disorder. The affected mitochondria appear to exhibit an age-dependent error catastrophe. It is possible that other genetic diseases might result in error catastrophes in mitochondria as well.  相似文献   
78.
Children represent a large underserved population of “therapeutic orphans,” as an estimated 80% of children are treated off‐label. However, pediatric drug development often faces substantial challenges, including economic, logistical, technical, and ethical barriers, among others. Among many efforts trying to remove these barriers, increased recent attention has been paid to extrapolation; that is, the leveraging of available data from adults or older age groups to draw conclusions for the pediatric population. The Bayesian statistical paradigm is natural in this setting, as it permits the combining (or “borrowing”) of information across disparate sources, such as the adult and pediatric data. In this paper, authored by the pediatric subteam of the Drug Information Association Bayesian Scientific Working Group and Adaptive Design Working Group, we develop, illustrate, and provide suggestions on Bayesian statistical methods that could be used to design improved pediatric development programs that use all available information in the most efficient manner. A variety of relevant Bayesian approaches are described, several of which are illustrated through 2 case studies: extrapolating adult efficacy data to expand the labeling for Remicade to include pediatric ulcerative colitis and extrapolating adult exposure‐response information for antiepileptic drugs to pediatrics.  相似文献   
79.
Perceptions of infectious diseases are important predictors of whether people engage in disease‐specific preventive behaviors. Having accurate beliefs about a given infectious disease has been found to be a necessary condition for engaging in appropriate preventive behaviors during an infectious disease outbreak, while endorsing conspiracy beliefs can inhibit preventive behaviors. Despite their seemingly opposing natures, knowledge and conspiracy beliefs may share some of the same psychological motivations, including a relationship with perceived risk and self‐efficacy (i.e., control). The 2015–2016 Zika epidemic provided an opportunity to explore this. The current research provides some exploratory tests of this topic derived from two studies with similar measures, but different primary outcomes: one study that included knowledge of Zika as a key outcome and one that included conspiracy beliefs about Zika as a key outcome. Both studies involved cross‐sectional data collections that occurred during the same two periods of the Zika outbreak: one data collection prior to the first cases of local Zika transmission in the United States (March–May 2016) and one just after the first cases of local transmission (July–August). Using ordinal logistic and linear regression analyses of data from two time points in both studies, the authors show an increase in relationship strength between greater perceived risk and self‐efficacy with both increased knowledge and increased conspiracy beliefs after local Zika transmission in the United States. Although these results highlight that similar psychological motivations may lead to Zika knowledge and conspiracy beliefs, there was a divergence in demographic association.  相似文献   
80.
This study challenges the prevailing view that marital companionship promotes marital satisfaction. By following a cohort of married couples for over a decade and by incorporating several methodological improvements—such as refining the measurement of marital satisfaction, determining how much spouses enjoy doing the leisure activities they pursue together and apart, and using diary data to portray marital leisure patterns—we found that the association between companionship and satisfaction is less robust than previously believed, and that it depends on how often spouses pursue activities that reflect their own and their partner's leisure preferences. Over time, involvement in leisure liked by husbands but disliked by wives, whether as a couple or by husbands alone, is both a cause and a consequence of wives' dissatisfaction.  相似文献   
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